Cut size continuous sheeter



Sept. 29, 1964 I. DALE ETAL 3,150,578

CUT SIZE CONTINUOUS SHEETER Filed July 23, 1962 5 Sheets-Sheet lINVENTORS ma vn L 0 H- E Jaw/1 (4/. CH5 WELL Sept. 29, 1964 I. DALE ETALCUT SIZE CONTINUOUS SHEETER 5 Sheets-Sheet '3 Filed July 23, 1962INVTORS may/a0 DflLE B JOHN MCnswzu.

E lllllcllllll FT JJ Q n w w Sept. 29, 1964 l. DALE ETAL CUT SIZECONTINUOUS SHEETER 5 Sheets-Sheet 5 Filed July 23, 1962 l 1 I l I I l l1 l l l l 5 i THE N m0 w k V S 0 W04" in m A W NW, wa y Y B UnitedStates Patent Qfficc 3,150,578 Patented Sept. 29, 1964 3,150,578CUT'SIZE CONTINUOUS SIEETER Ingvald Dale and John W. Caswell, Hoquiam,Wash, assignors "toLamb Grays Harbor 'C0., Inc., Hoquiam, Wash.

Filed July 23, 1962,Ser. No, 211,804 6'Claims. (Cl. 93-93) Thisinvention relates to what is herein designated a Cut 'Siz'e ContinuousSheeter. More specifically, the invention relates to a novel combinationof mechanisms that are operable for the high speed cutting, stacking anddischarging, without interruption, of reams of stacked paper sheets ofpredetermined count.

It is the principal object of this invention to provide a combination ofunitary mechanisms that are operable conjointly for the drawing of paperstrips into the cutting machine; for the high speed cutting of saidstrips as delivered thereto either singly or in multiples to producepieces of a predetermined size; for the even stacking of l the pieces assuccessively cut and for the delivery of the stacks from the machine inreams of predetermined count.

It is also an object of this invention to equip the sheet cuttingmechanism with novel means for the delivery of the cut paper sheetstherefrom at high speed, without clogging or jamming of the sheetfeeding 'or stacking mechanism; top'rovide a novel form of vibrating boxfor the reception of the cut-sheets for stack formation; to provide acontinuous l'ayboy for the stacking of the sheets and means for loweringthe ream stacks of predetermined count, as formed, from the stacking boxand then discharging them between deaer'ating belts which operate tosqueeze and roll out air from between the sheets and move the stack,without disruption to a. wrapping or packaging station.

Further objects and advantages 'of the present invention reside in thedetail of construction of the several unitary parts employed in thepresent combination and in their mode of operation as will hereinafterbe de scribed.

In accomplishing the above mentioned and other objects of the invention,we have provided the improved details of construction, the preferredforms of which are illustrated in the accompanying drawings wherein:

FIG. 1 is a side view of the machine, shown apart from the sheet cutter,embodying the improvements of the present invention therein,particularly illustrating the cut sheet feeding means, the sheetstacking box, the stack lowering means and the stack deaerating belts.

FIG, 1A is a cross section taken on line 1A1A in FIG. 1.

FIG. 2 is a central, longitudinal sectional view of the machine as seenin FIG. 1, taken in the Vertical plane of line 22 in FIG. 3. R

FIG. 3 is a top or plan view of the machine, as'shown in FIGS. 1 and 2.i

FIG. 4 is a side view of the rotary paper strip cutter as installed atthe receiving endof the machine of FIG. 1.

FIG. 5 is a plan view of the sheet cutter shown in FIG. '4.

FIG- 6 is the discharge end elevation of the machine of FIG. 1.

FIG. 7 is a longitudinal section of the paper strip cutter taken on line77 in FIG. 5.

FIG. 7A is an enlarged cross sectional detail on line 7A7A in FIG. 7.

FIG. 8 is a schematic showing of the pneumatic system for control of themachines operations. R

Referring more in detail to the drawings: To impart a betterunderstanding of the several units embodied in the present machine,their assembly, relationship and mode of operation, it will here beexplained that, as shown in the several assembly views of the drawings,the machine comprises a succession 'of cooperatively related andoperatively connected mechanisms that are individually designated intheir entireties as follows:

(1) A high speed rotary sheet cutter R shown best in FIGS. 5, 4, and 7.

(2) A 'feed section, designated in its entirety by reference letter Fwhich receives the sheets of paper as discharged from the rotary cutter.

(3) A vibrating stacking box V which receives the cut sheets of paperfrom the feed section and forms them into a stack.

(4) A stack deaera'ting seetion D which receives the stacks of paper ofpredetermined count and advances them after deaeration to a packaging'or' wrapping station.

The rotary cutter R herein shown might be one of any suitable kind andforin adapted to the present operation and no claim is made specificallythereto insofar as the rapid and continuous cutting of pieces ofspecified length from strips of paper fed thereto is concerned.

It has been shown in FIG. 7, that four strips of paper of the samewidth, designated, respectively, by reference characters, a, b, c, andd, are being simultaneously drawn from supply rolls, not shown, to thecutter R and are brought together therein and are cut thereby to properlength and the pieces delivered, four at a time, from the cutter ontothe downwardly sloping top run of the sheet conveyor beltsystem of thesheet feed section F for their conveyance and delivery thereby into thevibrating stacking box V.

It is further shown in FIGS. 1 and 4 that the rotary cutter R is mountedat the higher, right hand end of the rigid, main frame structure, of themachine. This frame structure preferably is fabricated of angle andchannel iron pieces. The cutter R is of unitary formation and issupported on laterally spaced, horizontal channel beams 12 which, in-turn, are supported by paired laterally spaced vertical legs 13,located at that end of said main frame structure. As best shown in FIGS.4, 5, and 7, the cutter R comprises the usual fly knife mounting reel14, equipped with a spirally directed knife or blade 14 that coacts, asthe reel revolves, with a fixed blade bar 15 to 'cut the paper stripsand discharge the pieces, as cut to exact length, onto the top run of asheet discharge belt 16 which, as best shown in FIG. 7, operates aboutparallel, driven rollers 17, 18 and 19, to deliver the cut sheets'endwise and ultimately to the feed section F of the machine.

Driving of the paper cutter R is effected by means of an electric motor20 that has a driving belt connection 21 with the drive shaft of the flyknife mounting reel 14, as shown in FIGS. 4 and 7. V

The discharge belt 16 of the cutter R is provided along its centrallongitudinal line with a continuous row of spaced perforations 25 and itis mounted for travel at its opposite ends about the roller 18 and 19with its top run sliding on and passing across the top wall 30 of avacuum chamber 31 that is fixed in the frame of the cutter; this topwall 30 being formed with a slit 32 with which the row of perforations25 of the belt 16 register in travel across the chamber, thus to applysuction through the belt perforation that will cause the sheets of paperas sheared from the strips to be drawn to and held against the belt andpositively fed thereby into thehigher, receiving end of the feed sectionF. The vacuum chamber 31 andslot 32 terminate short of the discharge endof belt 16 for release and discharge of the paper sheets from the beltinto feed section F.

The feed section F of the machine comprises a guideway that is supportedby and which extends along the top of the main frame structure at adownwardly sloping angle of approximately as well shown in FIG. 2 andthe sheet conveyor belt 33, as contained therein and onto which the cutsheets are delivered from belt 16 of the cutter R, slopes downwardlyaccordingly toward its discharge end to the receiving end of the sheetstacking box V.

It is seen in FIGS. 2 and 3 that the continuous belt 33 onto which thecut sheets of paper are discharged from belt 16, is disposed for travelin alignment with and along the longitudinal central plane of the cutterframe and feed section F; the belt guideway being defined by laterallyspaced parallel, opposite side plates 34-34. This belt 33 is ofsubstantial width and the sheets of paper as dropped thereon between theside plates 34-34 are carried thereby and delivered into the stackingbox which is mounted at the lower end of the belt guideway as seen inFIGS. 1 and 3.

The sidewalls 3434' of the sheet guideway are in fixed spacing and areequipped at the under edges of their higher end portions with shortdownwardly directed ears 36 that are bolted as at 37 in FIG. 1, to theupper ends of the laterally spaced legs 13 at that end of the machine,and, at their lower ends, are supported in fixed spacing on and by across-bar 38 that is fixed transversely of the main frame structure, asshown in FIG. 1, to the upper ends of laterally spaced vertical members13 at that end of the main frame.

The feed belt 33 is mounted at its receiving and discharge ends,respectively, for travel about transverse horizontal rollers 40 and 41which have trunnions at their ends revolubly mounted in bearings 42-42fixed to parts of the main frame structure as seen in FIGS. 1, 3 and 5.The trunnion at one end of roller 40 is extended and mounts a drivingwheel 43 about which a belt 44, operating from a driven belt wheel 45 orthe cutter mechanism, as in FIG. 5, is extended.

The vibrating ream forming box V into which the paper sheets aredischarged from belt 33 for stacking is defined by laterally spacedopposite sidewalls 46-46, see FIG. 3, extending substantially ascontinuations of the opposite walls of the guideway containing the sheetdelivery belt 33. The outer end of the box has a closing wall 47. Whenpaper sheets are discharged from belt 33 they are stopped by the endwall 47 and are dropped onto a horizontal box bottom plate 49.

During the stack forming operation, the box V is caused to be laterallyvibrated by a conventonal form of air operated vibrating devicedesignated by numeral 50, best shown in FIG. 3. This device 50 is seento be operatively attached at 45 degrees to the endwall 47 and to asidewall 46 to impart vibrations in both directions. Spring guides 5151are mounted to side walls 46, and form vibrating back guide to completebox for forming reams.

The plate 49 which serves as a bottom for the stacking box is supportedhorizontally on the upper end of the piston rod 58 that extends upwardlyfrom an air cylinder 58 mounted directly below the stacking box on thetop end of an air cylinder 58x as observed in FIG. 2.

It is seen in FIGS. 1 and 2, that the cylinders 58 and 58x are joinedend to end in coaxial alignment. Piston rod 58' extends from a piston58p fitted for travel in cylinder 58 and cylinder 58x is fitted with apiston 58" on a piston rod that extends downwardly and has supportingconnection at its lower end on a fixed block 58z.

The arrangement of cylinders 58 and 58x is best seen in FIG. 8. It isshown in FIGS. 1 and 2 that the cylinders joined end to end are movableendwise as a unit in a guide 59 fixed to the frame structure.

At the start of a ream cutting and stacking operation, the box bottomplate or table 49 is in its upper, or fully lifted position as shown indash lines in FIG. 2, but as the sheets of paper build up the stack onthis plate, it is caused to be slowly and gradually metered down by 4.downward travel of the joined cylinders, under control of meanspresently explained, thus to keep the top of the stack at a constantlevel.

When the forming stack reaches a predetermined count, a set of flat,bar-like fingers 60 are caused to be projected horizontally across itstop surface thus to catch and support the oncoming cut sheets of paperas they continue to be delivered from belt 33 into the box V. The formedstack on plate 49 is then quickly lowered to stack discharge level asindicated by the full line showing of the plate 49 in FIG. 2, and thestack is then pushed endwise from plate 49 between the stack deaeratingbelts of unit D as seen in FIG. 2, which are presently to be fullydescribed.

The stack supporting fingers 60 are all mounted in the same plane andare coextensive. They are fixedly supported by and extended forward fromthe forward end of a carrier frame 62 that is reciprocally slidable onand along a bar 63 that normally extends substantially horizontallybeneath the plane of travel of conveyor belt 33 and is fixedly mountedat its forward end in a supporting hanger bar 64 with pivotal mountings64' that permits the forward end of the bar 63 to be moved upward anddownward.

With the full lowering of a finished stack S as formed on the box bottomplate 49 to the discharged position, the stack 5 is then pushed endwisefrom the plate 49 as shown in FIG. 2, between a horizontally driven belt66, traveling across a horizontal table top 66' and a belt 67 thattravels about guiding rollers 68-68 and 69; this belt being backed by afixed plate 70. From roller 68' the belt 67 slopes upwardly to the beltdriving roll 69. Thus, as the stack 5 is received in the diverging mouthportion of the passage between the belts 66 and 67, which belts travelat the same speed, it is caused to be yieldingly compressed and any airthat may be trapped between sheets of the stack is thus caused to besqueezed out. As the deaerated stack passes from between these belts, itmay be conveyed by belt 66 to a place for storage, for wrapping orpackaging.

FIG. 2 shows belt 66 to be passed about and driven by a belt roller 72and belt 67 to be driven by power transmission belt 74 which hassprocket wheel driving connec tions with roller 72 and 69. It is alsoseen that the rollers 68-68 are mounted by a rigid swing frame 75 whichis pivoted on the supporting axis of roller 69 as shown in FIG. 2. Thebelt 67 travels across the underside of the flat backing plate 7 t)which is fixed in the frame 75 between rollers 68-68. The frame 75 isupwardly yieldable at its discharge end against a pair of springs 77mounted by a cross bar 78 fixed in the main frame structure as shown inFIG. 6, thus to yieldingly accommodate paper stacks of variablethicknesses, under a yieldable pressure. It is further to be explainedthat, after the fingers 60 have been extended to catch the cut sheetsdischarged from belt 33 into the stacking box V and While the firstformed stack is being lowered for delivery between the deaerating belts,the extended fingers are also caused to be gradually metered down. Thislowering of the fingers is under control of an air cylinder 80 supportedpivotally by a bracket 81 from a vertical leg of the main framestructure as in FIG. 2. The cylinder 80 is supported substantiallydirectly below the forward end of bar 63 and its piston rod 83 extendsupwardly therefrom and is connected pivotally by a link 84 with thesupport 65 that joins the vertically movable ends of the slide mountingbar 63. The regulated exhausting of air from the lower end of cylinder80 results in the metering down of the extended fingers 60 accordingly;the application of air under pressure to the lower end of the cylinder80 lifts the fingers, after retracttion, to their upper limit, as inFIG. 1.

The extending and retracting of the fingers 60 is controlled by an aircylinder that is mounted below and parallel with the bar 63 whichcarries the slide pate 62. It has a piston rod 91 extended to andattached to an arm 92 that extends down from the slide 62. Thus, whenthe piston rod is extended from the cylinder, the slide 62 is movedaccordingly to extend the fingers. When it is retracted, the fingers areretracted accordingly,

The ejection of a formed stack from the plate 49 to the deaerating beltsis effected by means, as shown in FIG. 2, to comprise an air cylinder 95fixed horizontally in the main frame structure below the level of theair cylinder 90. It has a piston rod 95 extended from its forward endthat mounts a push plate 96. When this piston rod is caused to beextended, the push plate engages the lowered stack S and moves itbetween the receiving ends of the deaerating belts '66 and 67 as hasbeen shown in FIG. 2. Then the piston and push plate are retracted tothe normal position of FIG. 1 while the belts 66 and 67 move the stackfor its deaeration.

The various air cylinders and devices are controlled in their functionsby valve means that can best be explained in connection with thediagrammatic showing of parts in FIG. 8.

A cycle of operations begins with cut paper sheets being rapidlydelivered from cutter R onto feed belt 33 from which they are dischargedinto the stacking box V and are dropped therein onto the box bottomplate 49 which is then at its fully lifted position of FIG. 1. As thestack builds up, this plate 49 is lowered accordingly by the controlledbleeding of air from cylinder 58x. When the stack reaches apredetermined count, as established by a counter, operated by directconnection with the cutter R, the stack discharge cycle begins. Theretracted fingers 60 are first caused to be extended across the top ofthe finished ream, by the admittance of air under pressure to the outerend of cylinder 90. As the fingers leave, valve 102 is shifted, whichstarts exhausting the air from cylinder 80 as shown in FIG. 1 togradually lower the fingers. When the fingers reach their fully extendedpositions, the finger mounting slide engages and acautes a valve 101 toenergize cylinder 58 to quickly lower plate '49 and the finished reamstack to its discharge level.

When the stack S reaches discharge level, the air cylinder 95 isenergized thus to extend its rod 95 and the push plate 96 to push thestack S from plate 49 to a position between the ends of the deaeratingbelt 66 and 67. The push plate 96 is then retracted by cylinder 95 tonormal position as in FIG. 1. This stack displacement is followed by theupward return of plate 49 to raised position, to receive the formingream from fingers 60 which are caused to be retracted and the stack ofsheets thereon deposited on the lifted plate 49 and the depositing ofsheets from belt 33 thereon continues to complete the stack to fullcount. The plate 49 immediately starts metering down.

In FIG. 8, we have shown electrical and air sequences and control asfollows:

A switch is actuated from Rotary cutter R, giving impulse to the counterfor each sheet or group of sheets cut. When a predetermined count hasbeen reached, relay 1 is energized and relay g is opened to de-energizesolenoid valve 112 which, in turn, actuates air cylinder 90 to extendthe fingers 60. As the fingers 60 move forwardly, valve 119 shifts andair is allowed to exhaust from cylinder 80 to lower the extended fingersas the stack builds up thereon. This causes the piston actuated valves114 and 118 to shift, thus exhausting the piston ends of cylinders 58and 58x.

When the fingers 60 reach their extended position, valve 117 is therebycaused to be shifted to actuate cylinder 58 to lower the box bottom 49to stack discharge position. As it moves down, the normally closedswitch TDS is opened which de-energizes and opens M and N which, inturn, tie-energizes i which closes g and opens I.

As the table 49 lowers to discharge position, valve 110 is shifted whichin turn shifts piston actuated valve 121 to actuate cylinder 95 toextend the pusherplate 96.

As pusher leaves, valve 116 shifts and connects port valve 130 and pilotof valve 132 to exhaust. When pusher 96 reaches extended position valve135 shifts, which in turn shifts piston actuated valve 132 which in turnexhausts pilot of valve 121 allowing it to shift and actuate cylinder toretract the pusher. In addition, piston actuated valve is shifted toready it for raising the table 49.

When table 49 reaches up position, normally open switch TUS is closed,which energizes K and closes M and N, which in turn energizes solenoidoperated valve 112 and actuates cylinder 90 which retracts the fingers60 and shifts piston actuated valve 130.

When fingers 60 reach retracted position, valve 119 is shifted, whichac-tuates cylinder 80 to return fingers to raised position and shiftsposition actuated valve 114 to exhaust air from cylinder 58x and starttable plate 49 to metering down. In addition, valve 118 is shifted tohold pressure on .piston end of top table cylinder 58 and rod end ofbottom cylinder 58x to make a positive metering down of table 49possible.

Manually operated valve 111 has been inserted to initially start table49 in the raised position. Valve 111 is shifted which in turn shiftspiston actuated valve 114 to actuate cylinder 58x to raise the table.

What we claim is:

1. A mechanism of the character described comprising in combination,means for successively delivering sheets of like size into a sheetstacking box; said box having an independently movable bottom on whichsaid delivered sheets are received to form a stack, means for loweringsaid bottom in the box in accordance with the building up of a stack ofsheets thereon, sheet catching means movable from a retracted positionoutside the box to an extended position Within the box directlyoverlying a stack formed on said bottom, to temporarily receive thedelivered sheets for stacking thereon during a time interval for removalof the formed stack from said box bottom, means operable for loweringthe box bottom and stack as formed thereon to a discharge level for theremoval of the stack from said bottom, means for returning the unloadedbox bottom to a position immediately below said extended sheet catchingmeans, another means operable incident to the return of the box bottomto initial position for retracting said sheet catching means from thebox and thereby depositing the sheets stacked thereon on said bottom andmeans operable to cause said sheet catching means, upon its beingextended, to be gradually lowered in accordance with the build up of astock of sheets thereon.

2. A mechanism according to claim 1 including, also, means for pushing aformed stack endwise from the box bottom when the box bottom has beenlowered to the stack discharge level, and a pair of driven, coactingconveyor belts is spaced to receive the stack endwise as pushed from thebox bottom between them and to progressively apply pressure to the stackas it is moved by and between said pair of belts for expulsion of airfrom between the stacked sheets.

3. A mechanism of the character described comprising in combination,means for successively delivering paper sheets of like size into a sheetstacking box; said box having dimension defining walls and anindependently movable bottom onto which said delivered sheets arereceived to form a stack, a support for the box bottom comprising onemeans associated therewith for causing said box bottom to be loweredthereby in accordance with the build up of a stack of sheets thereon andanother means for the quick final lowering of said bottom and stack to astack discharge level, means for actuating the support to return the boxbottom to its raised position, horizontally extending sheet catchingmembers supported for shifting from a retracted position outside thestacking box to an extended position, inside the box directly overlyinga stack forming on said bottom to temporarily receive incoming sheetsthereon during a period for the removal of the formed stack, means fordisplacing the formed stack from the box bottom when lowered todischarge level, means for actuating the box bottom support to returnthe unloaded bottom to its initial position, and means for causing theretraction of said sheet catching members from the box and theincidental depositing of stacked sheets therefrom on said bottom.

4. A mechanism according to claim 3 wherein said means for moving saidbox bottom between its upper and lower limits of travel comprises a pairof power cylinders mounted coaxially end to end and joined as a unit,each cylinder containing a reciprocal piston and piston rod, the rod ofone piston being extended downwardly to serve as a support for theassembled cylinders and the rod of the other being extended upwardlyfrom its cylinder as a mounting for the box bottom; said rods beingextendable from their cylinders by fluid pressure medium for theactuation to and support of the box bottom in its initial sheetreceiving position, a valve means for controlling the metered exhaustingof pressure medium from one of said cylinders for the lowering of theunit and box bottom in accordance with stack build-up and another valvemeans for a quick exhaustion of pressure medium from the other cylinderfor the quick final lowering of the unit and bottom to stack dischargelevel.

5. A mechanism according to claim 3 wherein said sheet catching membersextend from a slide that is reciprocally mounted on a horizontal bar,and wherein a pressure cylinder is operatively connected with said slidefor the extending and retracting of said members and a valve means isoperable upon delivery of a predetermined number of sheets onto the boxbottom for controlling an application of a fluid pressure medium to oneend of said cylinder, and another valve means is operable under controlof the return movement of the unloaded box bottom to its initialposition, to apply the pressure medium to the other end of the cylindersaid horizontal bar on which said slide is reciprocally mounted beingpivotally supported at one end for vertical movement of said sheetcatching members, and means is provided for moving said bar downwardlyat its mov- 8 able end to lower the extended catch members in accordancewith build up of a stack thereon and to lift it to normal position whenthe bottom is lifted back to its upper position.

6. A machine of the character described comprising in combination, meansfor the delivery of paper sheets of like size successively into a sheetstacking box, a sheet counter operable by delivery means; said stackingbox comprising dimension defining walls and an independently movablebottom onto which said sheets are received from the conveyor forstacking, a vertical support for the box bottom comprising two powercylinders joined end to end as a unit, with the piston rod of the lowercylinder extending downwardly to a fixed support and with the piston rodof the upper cylinder extended upwardly and mounting the box bottomthereon, valve means associated respectively with said cylinders forconrolling the application of a fluid pressure medium thereto to effectlifting of the box bottom to a top position to receive sheets from theconveyor, means for causing the valve means of the lower cylinder tometer out the pressure medium therefrom to maintain the top of the stackas formed, at a constant level, and means under control of said sheetcounter for quickly exhausting pressure medium from the top cylinderupon the building of the stack to a predetermined count to effect aquick lowering of the box bottom and stack to a discharge level, and astack pushing cylinder with control valve operable incident to the quicklowering of the box bottom to discharge position, to admit pressuremedium to the pushing cylinder to displace the stack from said bottom.

References Cited in the file of this patent UNITED STATES PATENTS1,997,965 Daly Apr. 16, 1935 2,413,556 Fourness et al Dec. 31, 19462,606,483 Forbes Aug. 12, 1952 2,641,974 Sperling et al June 16, 19532,819,661 Howdle et al. Jan. 14, 1958 2,934,221 Tonna Apr. 26, 1960

1. A MECHANISM OF THE CHARACTER DESCRIBED COMPRISING IN COMBINATION, MEANS FOR SUCCESSIVELY DELIVERING SHEETS OF LIKE SIZE INTO A SHEET STACKING BOX; SAID BOX HAVING AN INDEPENDENTLY MOVABLE BOTTOM ON WHICH SAID DELIVERED SHEETS ARE RECEIVED TO FORM A STACK, MEANS FOR LOWERING SAID BOTTOM IN THE BOX IN ACCORDANCE WITH THE BUILDING UP OF A STACK OF SHEETS THEREON, SHEET CATCHING MEANS MOVABLE FROM A RETRACTED POSITION OUTSIDE THE BOX TO AN EXTENDED POSITION WITHIN THE BOX DIRECTLY OVERLYING A STACK FORMED ON SAID BOTTOM, TO TEMPORARILY RECEIVE THE DELIVERED SHEETS FOR STACKING THEREON DURING A TIME INTERVAL FOR REMOVAL OF THE FORMED STACK FROM SAID BOX BOTTOM, MEANS OPERABLE FOR LOWERING THE BOX BOTTOM AND STACK AS FORMED THEREON TO A DISCHARGE LEVEL FOR THE REMOVAL OF THE STACK FROM SAID BOTTOM, MEANS FOR RETURNING THE UNLOADED BOX BOTTOM TO A POSITION IMMEDIATELY BELOW SAID EXTENDED SHEET CATCHING MEANS, ANOTHER MEANS OPERABLE INCIDENT TO THE RETURN OF THE BOX BOTTOM TO INITIAL POSITION FOR RETRACTING SAID SHEET CATCHING MEANS FROM THE BOX AND THEREBY DEPOSITING THE SHEETS STACKED THEREON ON SAID BOTTOM AND MEANS OPERABLE TO CAUSE SAID SHEET CATCHING MEANS, UPON ITS BEING EXTENDED, TO BE GRADUALLY LOWERED IN ACCORDANCE WITH THE BUILD UP OF A STOCK OF SHEETS THEREON. 